Introduction

The Marble Loaf Cake is a delightful blend of rich chocolate and classic vanilla flavors swirled together in one moist loaf. Perfect for anytime indulgence, this cake is topped with a luscious chocolate ganache that adds an elegant touch. Whether for a special occasion or a simple treat, it’s sure to impress.

Ingredients

2 cups (250g) all-purpose flour (spooned & leveled)

1 teaspoon baking powder

1/2 teaspoon baking soda

1/2 teaspoon salt

3/4 cup (12 Tbsp; 170g) unsalted butter, softened to room temperature

1 and 1/4 cups (250g) granulated sugar

3 large eggs, at room temperature

1 Tablespoon pure vanilla extract

1 cup (240g/ml) buttermilk, at room temperature and divided

1/2 teaspoon espresso powder

1/4 cup (21g) Dutch-process cocoa powder

4-ounce (113g) quality semi-sweet chocolate bar, finely chopped

6 Tablespoons (90g/ml) heavy cream or heavy whipping cream

Optional: fresh raspberries and mint sprigs, for garnish

Instructions

Step 1: Preheat the oven to 350°F (177°C) and generously grease a 9×5-inch loaf pan.

Step 2: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.

Step 3: Using a handheld or stand mixer fitted with a paddle attachment, beat the butter and sugar on medium speed until light and fluffy, about 5 minutes. Scrape the bowl as needed. Add the eggs and vanilla, then beat on high speed for 1 minute. It’s normal if the mixture looks a bit curdled.

Step 4: Pour the flour mixture into the wet ingredients. On low speed, slowly add 3/4 cup plus 2 Tbsp (210g/ml) of the buttermilk while mixing. Beat just until combined; avoid over-mixing. Whisk by hand if needed to remove lumps. The batter will be slightly thick.

Step 5: Transfer just under half of the batter to another bowl. Warm the reserved 2 Tbsp buttermilk for 10–15 seconds, then stir in espresso powder until dissolved. Pour this into the batter bowl with less batter. Sprinkle cocoa powder on top and stir or beat on low speed until combined.

Step 6: Spread a thin layer of the plain vanilla batter in the bottom of the prepared loaf pan. Alternate spoonfuls of chocolate and vanilla batter over it, layering until all batter is used. Gently shimmy the pan to level the batter.

Step 7: Using a knife, make rounded horizontal zig-zag swirls across the batter, then make rounded vertical zig-zag motions to create the marble effect.

Step 8: Bake for 65–75 minutes, until a toothpick comes out clean. If the cake browns too quickly, tent with foil after 30 minutes. Start checking after 55 minutes since oven times vary.

Step 9: Cool the cake in the pan on a rack for 30 minutes, then remove it from the pan and cool directly on the rack.

Step 10: For the ganache, place chopped chocolate and cream in a heat-safe bowl over simmering water. Stir frequently until smooth and melted. Remove from heat and let cool for 20 minutes or until slightly thickened.

Step 11: Drizzle or spread the ganache over the cooled cake. Serve slightly warm for a soft topping; it will firm up to a fudge-like consistency after several hours.

Step 12: Garnish with fresh raspberries and mint sprigs if desired before serving.

Tips & Variations

Use room temperature eggs and butter to ensure a smooth, well-emulsified batter.

Espresso powder enhances the chocolate flavor but can be omitted for a milder taste.

Swap out semi-sweet chocolate for dark chocolate for a richer ganache.

Try adding chopped nuts or swirl in some peanut butter for a twist.

FAQs

Can I make this cake without buttermilk?

You can substitute regular milk mixed with 1 tablespoon of lemon juice or vinegar per cup, let it sit for 5 minutes to curdle, then use it as a buttermilk replacement.

How do I know when the cake is done baking?

Insert a toothpick into the center of the cake; it should come out clean or with a few moist crumbs. If batter sticks to the toothpick, bake a little longer and check again.